Frost, Alfred Sidney, 1858-1922.

Military officer, college professor.

Frost moved to Brookings in 1893 where he was a professor of Military Science and Tactics at the South Dakota Agricultural College. While at Brookings he was also admitted to the bar. In 1896 Frost became an instructor for the South Dakota National Guard. By a special act of the 1897 legislature, Frost was made Military Secretary to the Governor, with the rank of colonel in the National Guard.

At the outbreak of the Spanish-American War, Frost was commissioned colonel of the First South Dakota Infantry and led the regiment in the Philippines. On 14 December 1898 he was promoted to Captain of the Twenty-second United States Infantry.